Me pēhea te hanga i tētahi reo irirangi me te āheinga whakarārangi ā-ringa
Ahakoa te ahua o te reo irirangi he hangarau "matarohia", koinā tonu tōna āhua. Ahakoa tōna māmā noa iho, he taputapu hiko te reo irirangi e whakakotahi ana i ngā ariā o ngā ngaru hikohiko, te haruru, te whakanui tohu, me te whiriwhiri auau. He kaupapa ngahau, he kaupapa ako hoki te hanga i tō ake reo irirangi—ina koa ko tētahi he āheinga whakahāngai ā-ringa. Mā te whakahāngai ā-ringa, ka taea e koe te huri i tētahi porowhita hei kimi i tētahi teihana, te wheako i te harikoa o te "hopu" i tētahi pāhotanga, me te mārama ki te whiriwhiringa o ngā auau me te kore he āwhina o te matawai aunoa.
Ka hipokina e tēnei tuhinga ngā ariā, ngā wāhanga, me ngā mahi whānui mō te hanga i tētahi reo irirangi māmā me te whakahāngai ā-ringa. Ka arotahi mātou ki ngā kaiwhiwhi reo irirangi AM (Amplitude Modulation) nā te mea he māmā ake te hanga, ā, he pai hoki mō te hunga tīmata.
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1. Kia Mārama ki te Mātāpono Mahi o te Whakatūnga Reo Irirangi ā-Ringa
E toru ngā mahi matua a te reo irirangi:
1. Hopukia ngā tohu reo irirangi mā te whakamahi i tētahi pūihi.
2. Te tīpako i tētahi auau motuhake mai i ngā tohu maha e tae mai ana (koinei te mahi whakahāngai).
3. Ka huri i te tohu hei oro, ka whakanuia hoki kia rangona i runga i ngā kaikōrero, i ngā taringa rānei.
I roto i te whakahāngai ā-ringa i te reo irirangi, ka whakamahia he ara iahiko LC hei whiriwhiri i te auau—he huinga o te inductor (L) me te capacitor (C). Ina hurihia e koe te porotiti whakahāngai, ka hurihia te uara o te capacitor (he capacitor taurangi te nuinga), ā, ka hurihia te auau oro.
Tātai auau haruru:
\[
f = \frac{1}{2\pi \sqrt{LC}}
\]
Arā, mā te whakarerekē i te C, ka whakarerekētia hoki te f, ā, ka tīpakohia e te reo irirangi te teihana e ōrite ana te auau.
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2. Whakatauhia te momo reo irirangi ka hangaia
He maha ngā kōwhiringa hoahoa:
– Reo irirangi karaihe (kāore he pākahiko): te mea māmā rawa, engari he ngoikore te tangi, ā, me whakamahi he pūihi roa.
– He reo irirangi AM māmā me te whakakaha oro: he māmā tonu engari he kaha ake te oro nā te mea he whakakaha e whakamahia ana.
– Superheterodyne: he kounga pai, engari he uaua ake mō te hunga tīmata.
Mō tēnei kaupapa kupu 1000, ko te kōwhiringa pai ko te reo irirangi AM me te whakahāngai ā-ringa me te whakakaha oro. He "ā-ringa" te āhua o te whakahāngai, ā, ka rangona ngā hua mā roto i ngā kaikorero iti.
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3. Ngā Wāhanga e Hiahiatia ana
Anei te rārangi o ngā wāhanga e whakamahia whānuitia ana:
Wāhanga whakahāngai me te whiwhi tohu
– Pūngao taurangi (pūngao taurangi) tata ki te 10–365 pF (he mea noa i roto i ngā reo irirangi AM)
– Inductor/coil. Tae:
– te koiri kua rite ki te whakamahi (koiri pūihi ferrite AM), rānei
– hangaia tāu ake me te waea enamel i runga i te tokotoko ferrite
– Te taiohiko tirotiro (hei tauira, te germanium 1N34A; hei tauira, te 1N60, te Schottky rānei pērā i te BAT43)
– Ngā pūnga iti mō te tātari (hei tauira, 10 nF–100 nF)
– Ngā ātete o ngā uara rerekē (hei tauira, 10k–100k) i runga i te hoahoa
Wāhanga oro (whakakaha)
– IC whakakaha oro māmā, hei tauira:
– LM386 (tino rongonui mō ngā kaupapa reo irirangi iti)
– Pūmana rōrahi 10k
– He kaikorero iti, he taringa rānei, he 8 ohm te kaha
– Ngā pūnga hikohiko mō te hononga (hei tauira, 10 µF, 100 µF)
– Pūtake hiko pākahiko 9V, 3–6V rānei (kei te whirihoranga)
Ngā taputapu huihuinga
– Papa parāoa, PCB rānei, he kōhao ōna
– Te tūhono me te tine (mēnā kua oti te huihui whakamutunga)
– Ngā taura pekepeke
– He poro hei whakahāngai (kāore he kōwhiringa engari ka ātaahua ake)
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4. Te Waihanga i te Wāhanga Whakatū (LC) mō te Kōwhiringa Auautanga
Ko te wāhanga tino nui o te whakahāngai ā-ringa ko te ara iahiko tāke LC. Ko te huarahi māmā rawa atu:
1. Whakamahia he pūnga iahiko taurangi hei C.
2. Whakauruhia te koiri (L) e tika ana mō te roopu AM (tata ki te 530–1600 kHz).
Kōwhiringa 1: Te whakamahi i tētahi porowhita pūihi ferrite AM kua oti te hanga
He maha ngā reo irirangi AM tawhito he koiri kei runga i ngā tokotoko ferrite. Ka taea e koe te whakamahi i ēnei nā te mea he pai mō te whānuitanga AM, ā, he ngāwari ki te whakahāngai mā te whakamahi i tētahi pūngao taurangi.
Kōwhiringa 2: Hangaia tāu ake koiri (tata tonu)
– Whakaritea he tokotoko ferrite (ka taea te whakamahi i tētahi reo irirangi kua whakamahia).
– Whakamahia he waea enamel 0,2–0,5 mm te matotoru.
– Kia 60–100 ngā hurihanga o te hau (ka rerekē i runga i te ferrite me te capacitor).
– Waihangahia he peka (pā) ki te hiahia koe ki te whakamātau i te aro.
I te mea he rerekē ngā wāhanga tūturu, me whakamātau koe i ētahi tau takai kia pai rā anō te awhe whakarārangi.
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5. Wāhanga Pūoko: Te Tahuri i ngā Tohu RF ki te Ororongo
He ngaru auau-teitei tonu te tohu AM kua hopukina. Hei huri i tēnei hei oro, ka whakamahia he taputapu kite kōpaki:
– Ka haere te putanga o te ara iahiko LC ki te diode.
– Ka whakatikahia te tohu e te diode kia taea ai te tango i te "arai" oro.
– Mā te pūnga iti ka āwhina i te whakawhāiti i te tohu RF kia noho ko te wāhanga oro anake te mea e toe ana.
He maha ngā wā ka whiriwhiria ngā taio Germanium nā te mea he iti te ngaohiko whakamua, ā, ka nui ake te aro ki ngā tohu ngoikore. He pai anō hoki ngā taio Schottky hei kōwhiringa kē.
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6. Tāpirihia he Whakakaha Oro (LM386) mō te Oro Kaha
Ki te kore he whakakaha oro, ka mārie te tangi o te pūoko (he rite ki te reo irirangi karaihe). Nō reira, tāpirihia he whakakaha oro māmā pēnei i te LM386.
Te kaupapa whānui:
– Ka whiwhi te tāuru LM386 i te tohu oro mai i te putanga o te pūoko mā roto i te pūnga honohono (hei tauira, 10 nF–100 nF, 1 µF rānei, i runga i ngā whakaritenga).
– Ka mahi te pūmana 10k hei rōrahi.
– Ka tukuna te putanga LM386 ki te kaikorero mā roto i tētahi pūnga hikohiko (ko te tikanga he 220 µF, he 470 µF rānei).
– Tāpirihia he pūnga hiko karo (hei tauira, 100 nF) ki te taha o te pine hiko hei whakaiti i te haruru.
Ma tenei, ka rangona mārama te reo irirangi i runga i nga kaikorero iti, ina koa mena he kaha rawa nga teihana AM i to rohe.
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7. Ngā Hipanga Huihuinga i Manakohia
Hei whakangawari ake, hei whakaiti hoki i te hoha, me mahi i roto i ngā wāhanga:
Hipanga 1: Huihuia ngā wāhanga whakarārangi + pūoko i te tuatahi
– Tāutahia te LC (kōiri + pūnga whakapūnga rerekē).
– Honoa te diode me te pūnga tātari.
– Whakamātauria te whakarongo ki te putanga oro me ngā taringa ārai teitei (mēnā kei a koe tētahi) me te whakamahi rānei i tētahi whakakaha oro māmā.
Ko te whāinga kia taea e koe te "hopu" i te pāhotanga ina tahuri koe i te whakahāngai.
Hipanga 2: Tāpirihia te whakakaha LM386
– Huihuia te LM386 ki runga i te papa parāoa.
– Whakakahangia te pākahiko.
– Honoa te oro mai i te pūoko ki te tāuru LM386.
– Tāutahia te kaikorero me te pūmana oro.
Hipanga 3: Whakaritehia te tahora
He tairongo ngā reo irirangi ki te haruru me te tūnga o te taura. Tohutohu:
– Kia poto rawa te taura i te wāhanga LC.
– Puritia ngā wāhanga RF (LC, diode) kia matara atu i ngā taura putanga kaikorero e kawe ana i ngā iahiko teitei ake.
– Tāutahia he pūnga hiko karo ki te pūtake hiko tata ki te IC.
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8. Ngā Tohutohu Whakatū Ā-ringa hei Hopu Ngāwari i ngā Teihana
1. Whakamahia he pūihi pai
Mō te AM, he rawaka te pūihi ferrite, engari i ētahi wā ka āwhina te torutoru mita o te pūihi waea i ngā wāhi ngoikore o te tohu.
2. Tahurihia mārire te whakarārangi
He kuiti te hongere AM i ētahi wāhi. Hurihia mārire i a koe e whakarerekē ana i te oro.
3. Whakaitihia ngā pūtake o te pokanoa
Ka taea e ngā rihi utu iti, ētahi rama LED, me ngā pona te whakararuraru. Ngāna kia matara atu te reo irirangi i ngā pūtake o te pokanoa.
4. Whakamahia he whenua māmā
I ētahi wā, mā te hono i te whenua o te ara iahiko ki tētahi paipa wai/whakarewa nui ka āwhina i te hopu (kia tūpato, kia mau hoki).
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9. Te Whakawhanaketanga Anō
Kia mahi te reo irirangi, ka taea e koe te whakawhanui:
– Tāpirihia he mata whakarārangi me te tauine auau.
– Hangaia he anga mai i te kiriaku, te rakau, te tānga 3D rānei.
– Whakamātauria tētahi atu roopu oro (hei tauira, FM), engari me whakamahi i tētahi ara iahiko uaua ake.
– Tāpirihia he atamira whakakaha RF i mua i te pūoko kia nui ake ai te tairongo.
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Te Katinga
He huarahi ngahau te hanga i tētahi reo irirangi me te āheinga whakahāngai ā-ringa ki te mārama ki ngā kaupapa matua o ngā whakawhitiwhiti kōrero reo irirangi. Ka ako koe i tēnei kaupapa mō ngā ara iahiko LC resonance, te kimi AM me ngā diode, me te whakanui oro mā te whakamahi i ngā IC māmā pēnei i te LM386. Haunga te whakarato i ngā hua tūturu—he reo irirangi e hopu ana i ngā pāhotanga—ka whiwhi hoki koe i tētahi māramatanga mahi mō te mahi a te hangarau reo irirangi mai i ōna rā tuatahi ki tēnei rā.
Ki te hiahia koe, ka taea e au te āwhina me tētahi mahere ara iahiko motuhake ake, he taunakitanga mō te maha o ngā hurihanga koiri i runga i te pūnga iahiko taurangi kei a koe, he aratohu tahora papa taro/PCB rānei mō ngā hua pumau ake me te iti o te haruru.
